Question 5 of 10 Why are magnetic materials attracted to magnets?
A. They become permanent magnets when they are in a magnetic
field,
B. They become temporary magnets when they are in a magnetic
field.
C. They are temporary magnets whether or not they are in a magnetic
field.
D. They are also attracted to Earth's magnetic field, which is always
present

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.